Maura had just gotten off the phone with Katherine when she entered Jane's office.

Jane looked at her wife in surprise and took her reading glasses off her nose. "Maura, what's up."

"I've been thinking about what Samantha Conway said, the woman who was in the killer's grip and has now died in the hospital."

"Died? Or was she murdered?" replied Jane with a frown.

"More likely the latter. Maggie will be able to tell soon enough." She joined her wife at the desk. "Samantha Conway told Liz that the man who held her captive was younger, and his voice would sound very different from a drunkard like Burns was."

Jane was now bright-eyed and lifted her chin. "So what?"

Maura had brought a stack of files. "Kate and I had the idea to go back to the court and look at the files to see who else was present at Burns' trial." She put a hand on the files and frowned a little. "One of my assistants pulled these files together. Went faster than I thought." She spread the files out in front of Jane and added another to the pile on the desk. "There was another boy," she said with a frown. "Michael Hebert. He was Chantal's son, whose murder or assault resulting in death was at issue in the trial."

Jane was now more than bright-eyed and closed her laptop. "Kevin Burns wasn't the boy's father?"

Maura took a deep breath and looked piercingly at the chief. "No, he was the mother's new boyfriend, and the boy's biological father, Kyle Heber, had died about a year earlier."

Jane put her reading glasses back on before taking the top file from the stack and opening it. "Was he on the bottle, too?"

Maura nodded slowly, crossing her legs as usual. "Yes, you have the file. The autopsy report." She pointed to a picture showing Kyle Hebert's abdomen swollen with water due to liver malfunction. "His liver was just a hardened ball, and a plum-sized, slimy tumor was growing in his mouth. Even if he had wanted to ... he wouldn't have been able to eat solid food."

Jane screwed up her face.

"But that's not all," Maura continued. "Varicose veins formed in his esophagus from all the drinking, and they burst. Hebert has been spitting up large amounts of blood because of this, and the blood shoots out of his mouth with such pressure that it splashes up to the room's ceiling."

Jane looked over the rim of her glasses. "Jackson Pollock says hello."

"Here's another picture." Maura pulled a picture out of the file. It showed the man lying like a dead fish on the bathroom floor in a sea of blood. "That's how the boy discovered his father. Dead and bleeding to death. The walls, the floor, the ceiling, all covered in blood."

"Jesus," Jane muttered as she studied the picture. "How did the boy put this away?"

Maura leaned back in her chair and licked her lips. "Against all odds, well, it seems. He was relieved when his father died. But then Burns came along. And Burns was worse."

Jane gritted her teeth and fixed her wife. "And he beat up the mother?"

Maura nodded slowly, with her lips pressed together, indicating that she finally remembered the court case. "Yes. He was the one who beat the little boy's mother to death." She handed the chief another file. "Here's the autopsy report."

Jane looked at the attorney for a long moment before her gaze flitted over the text. "Fractured skull and neck."

Maura took a deep breath and nodded slowly. "Yeah, the son of a bitch pushed her down the stairs and then kicked her in the head to boot."

Jane dropped the file on her desk and furrowed her brows. "Did the kid see that, too?"

The prosecutor hesitated a moment. "Worse."

Jane's eyebrows drew together. "What do you mean?"

Maura pulled out another file and took a deep breath. "This excerpts the indictment and a report from the police department in charge. According to it, the boy dragged his dying mother up the stairs back into the apartment. And then --" she lowered her voice, and you could see the horror even on her face, "... the boy lay with his dead mother the whole night. The night and part of the day." She looked at the file again, although she knew the contents by heart. "The neighbors saw the mother's blood trail leading down the stairs into the apartment in the morning and called 911. And the cops then found the boy. Tightly embraced in the hallway with his dead mother, covered in blood and tears." She licked her lips again. "He was in denial that his mother was gone."

Jane gasped and shook her head slightly. "Let me guess. There was a trial. And the killer, this Burns guy, got parole. Wasn't he even found not guilty because of insanity?"

Maura nodded slowly. "Yes. Twelve weeks of mandatory rehab and insanity for alcohol consumption."

"Could that be a motive?" asked Jane, looking at her wife long and hard.

Maura took a deep breath and frowned deeply. "We thought Burns was the killer killing everyone involved in the process. More specifically, the killer makes people suffer in which, he seeks revenge by making them witness the death of a loved one. And as it seems, they then have to stay with the corpses, putting coins under their tongues and the like. Sort of a funeral ritual, to quote Kate." She shook her head. "But such a perfidious murder doesn't suit a clumsy drunk like Burns. Nor to the victims. And certainly not with the punishment."

"And the victims," Jane narrowed her eyes, "stay with the bodies of their loved ones, just as the boy did with his dead mother that time, where he held a kind of wake. Everything that boy had to suffer, those who touched his mother's killer too gently must suffer, too."

Maura pursed her lips and nodded. "And that could very well be a motive."

"How old is this boy now?" the chief wanted to know.

"He was six years old at the time of the crime. Then he's now --" Maura did some quick math in her head. "Twenty-three."

"A little young for a murderer, isn't he?"

"Actually, yes," the lawyer said, shrugging her shoulders. "But we know of children who are much more mature and advanced than others in their age group because of traumatic experiences in childhood. Child soldiers from the Congo, for example, when they become adults. Or children from slum areas who have been through terrible things. Or someone like Michael Hebert. Although physically still children, they are mentally adults. At thirty, they are like others at fifty. And they're perpetually paranoid, as Kate put it."

"That means Michael Hebert could be planning things like this at twenty-three?" Jane pointed to a picture on her pinboard that showed Frank Conway's body with his arteries cut open.

"Oh, yes," Maura replied, frowning again. "Kate said it was unusual but possible. He watched his birth father die in a lake of blood. He's been through hell with Burns and watched his mother die and lain with her corpse. And then, the court also gave him the middle finger and let the killer go. That's formative." She moved closer to the desk. "He's three times as far along at twenty-three-and ten times as dangerous as the giant babies of our time who still live at home at thirty-five."

Jane picked up her empty coffee cup and furrowed her brows. "Where did they live? I mean Hebert, Burns, and company, not the giant babies."

"In Mattapan," Maura replied, suppressing an eye roll before doing so. "A problem district even back then."

Jane rose from her chair and headed for her coffee maker. "Do me a favor and give that info to Nick. We need to find out where this Michael Hebert lives right now. And call Liz, and get her over here as soon as possible."

xxx

Elizabeth drove out of town across the highway at a fast pace, looking strained at the road, trying not to let Carl lose her. He probably knew something. But ambitious as he was, he didn't want to share his knowledge with anyone but take credit for it himself.

The cell phone rang, and it was the number for the ME's office, Maggie.

"Rizzoli," the detective answered.

"News," Maggie said. "It's Samantha Conway. The lab ran the comb you brought us from the hospital, and the DNA matches what CSRU found and was at the scene."

"And what did she die of?" wanted Elizabeth to know with a furrowed brow. "Was it foul play or homicide?"

"People always claim," Maggie said instead of an answer, "that air is invisible in the heart. And that you could kill someone by injecting air into a vein. But that's not true."

"Are you talking about Samantha Conway, Mags?" asked Elizabeth. "Did someone inject air into her vein?" She looked at the road with one eye and her cell phone with the other. Not long now, and the battery was dying.

"Yeah," said Maggie, standing at the autopsy table with a dissection assistant. On the table was the body of Samantha Conway. "That's what we suspect."

"Can we get to the point?" growled Elizabeth. "I'm on my way, and my cell phone is about to die." She rummaged in the glove compartment but couldn't find the charging cable that would allow her to charge the phone.

Undeterred, Maggie continued to speak. "We've run the body through CT before. I could email you the picture, but your phone finally gives up. You can see a black bubble in the heart in the picture."

"So what?"

"Black means air, Liz."

"Don't we get that a lot? Even with decomposing bodies?"

"Right," Maggie said, nodding for her assistant to open the body's chest. The dissection assistant cut a long path from the neck to the pubic bone, unfolding the skin to the right and left. Then he picked up a pair of rib shears to cut through the ribs and get to the heart.

"But then with decomposing bodies," the redhead continued, "we also have air in the intestines, the liver, and the large vessels, the main arteries. Here we don't have all that, and here it's only in the heart. Also, the body is still fresh and warm, and the residual heat is still palpable. Rib shears, please."

Fresh and warm. In Elizabeth's opinion, this euphemism was more appropriate for buns, not corpses.

The assistant pinched the ribs with the rib shears. The detective heard the crack even through his cell phone.

"We're doing something nice here now. The method is probably two hundred years old, but still works very well," Maggie said after a brief pause. "We've just cut open the chest and severed the ribs. The heart of the dead is in front of us, embedded in the pericardium, also called the pericad. That's the sac of connective tissue that surrounds the heart and allows it some kind of ... let's say, mobility."

"Why is that important?" Elizabeth stared intently down the road, feeling under her seat to ensure the charging cable wasn't there.

"We're going to prove right now - live, so to speak, with you on the phone - that Samantha Conway died of an air embolism, which is lifted in the heart."

Elizabeth fretted over Maggie's long-windedness and hoped her cell phone would hold out a little longer. "Well, fire away, Mags."

Air in the heart, the detective knew, led to heart fibrillation and cardiac arrest. The heart that could no longer beat. It was like a heater with air around the heating pipe. The plumber had to come. Only with humans was everything then too late. There was no plumber in such cases, only the mortician.

"Do you remember how they used to patch a tire on a bicycle? When they found where the hole was in the bicycle tube?"

Elizabeth wondered at the question. "Ma used to hold the bicycle tube in a bucket, and where air bubbles came out was where the hole was."

"And that's exactly what we're doing now."

Maggie described the procedure to her wife while the assistant cut the pericardium open Mercedes-star style and held the three ends of the bag up with forceps. At the same time, Maggie filled a plastic container. Which the contents of the stomach would usually be dumped with water and then carefully poured the water into the pericardium. Then she raised a long, pointed knife.

"The pericardium is now in the bucket of water," the redhead said, "the heart is the bicycle tube. And the leak ... well, we'll do that ourselves now. It's not like we want to know where the hole is; we want to know if there's air in the heart." She stabbed the knife into the right ventricle. Air bubbles bubbled out of the heart and came to the surface through the water in the pericardium. "Positive," she said. "The air that's coming out now, someone injected it. When the air gets into closed systems, those systems break down. The woman died of an air embolism, and someone injected air into her catheter.

It must have been the killer, Elizabeth reasoned. So she couldn't reveal more. The killer had been close by at the hospital, and maybe Carl had even seen him. "All right," she said, resigned to the fact that she couldn't find the charging cord. "I still have to call Ma. Please make sure the entire trash can in Samantha Conway's hospital room is confiscated, okay? If we're lucky, there's still the damn syringe she was killed with, and if we're even luckier, there might be skin particles or fingerprints on it."

"Already on it. I'm afraid," Maggie said, "our killer isn't that stupid."

Elizabeth took a deep breath. "I'm afraid so, too. But hoping is better than fear." With that, she ended the call and called Jane.